However, the phone cares deeply about the state of charge of its internal battery*. Even though it is connected to the car kit, and has a continuous source of power, it worries incessantly about electricity issues. If it gets down to 99% charge, it starts recharging. And when it finishes charging, it notifies me by beeping and displaying a "battery full" message.
To dismiss this helpful and informative message (which appears a few times an hour while driving), I have to open the phone (displaying the same message, and assigning the "OK" function to the "enter" key), and press the (tiny) "enter" key. This is not really something safe to attempt whilst driving.
UNFORTUNATELY, the voice dialing feature is disabled while the phone is in this state. Mashing the big button only results in a disappointed-sounding "boop" noise, with no explanation. This rather defeats the safety and convenience of voice dialing. Bad engineering! No engineering biscuit! Bad Nokia!
I wrote Nokia to complain about this, but their reply only told me that I'm required to "confirm" the "Battery full" message. Fail.
Now, if only there were a nice rugged GSM cellphone with Bluetooth that works well with a car kit and an external antenna jack or coupler.
* Technically, it's a cell, not a battery, but the phone (and most people) refer to it as a "battery", so I will here.